Rahu (north lunar node) and Ketu (south lunar node) are not real planets, but they carry immense power in KP. They are agents—stand-ins for planetary significations they occupy or lord.
Agent rule: Rahu/Ketu inherit the significations of the planet whose sign they occupy. If Rahu is in Virgo, Rahu acts as an agent for Mercury (Virgo's lord). If Ketu is in Scorpio, Ketu acts as an agent for Mars (Scorpio's lord, in classical; or Mars+Ketu in KP, requiring the stronger of the two).
Influence modifier: Rahu is amplifying, destabilizing, foreign-bringing, illusion-generating. Ketu is separating, releasing, past-related, spiritual. An event governed by Rahu often manifests as unexpected, comes from outside, or involves a detour. An event governed by Ketu often involves endings, release, or spiritual learning.
Example: 7th house (marriage) cuspal sub-lord is Rahu (acting as Mercury agent). Marriage might come through communication, a foreign country, or unexpected connection. But Rahu's involvement suggests delay or an unconventional path.
Hierarchy: If Rahu tenants a house but the planet it agents for does not, Rahu's promise overrides. But if both Rahu and the agented planet are present, Rahu's influence modifies the planet's promise (often by delaying or complicating it).
The engine identifies Rahu and Ketu's agented planets and flags their involvement in significator outcomes. You will learn to incorporate Rahu/Ketu's shadowiness into your predictions, upgrading from "marriage will happen" to "marriage will happen, likely via a foreign connection or unconventional meeting."
Why the nodes are special. Rahu and Ketu are computed points, not bodies, and they own no sign. Classical astrology handles this by assigning them co-rulerships or by reading them through their dispositors. KP formalises the idea: a node acts as an agent, delivering the results of other planets rather than results of its own.
The order of agency. A node represents, in order: any planet conjoined with it, its star lord, and the lord of the sign it occupies. When several of these apply, the node's behaviour blends them, which is why nodal periods often feel mixed or contradictory in a way other periods do not.
Why agents can be strong. Acting on behalf of a principal, a node frequently delivers that principal's results more forcefully than the principal would alone. This is the origin of the observation that nodal dashas produce sudden or exaggerated events. It is not that the nodes have their own agenda; it is that agency amplifies.
Practical caution. Because a node's meaning is entirely borrowed, misidentifying its star lord or dispositor corrupts the whole reading of that node. Check these before interpreting any nodal placement, and be explicit about which planet the node is representing when you explain the reading.